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DOI	10.1016/j.epsl.2020.116150
	Prompt elasto-gravity signals (PEGS) and their potential use in modern seismology
	Zhang S.; Wang R.; Dahm T.; Zhou S.; Heimann S.
发表日期	2020
ISSN	0012821X
卷号	536
英文摘要	An earthquake causes a sudden rock-mass redistribution through fault rupture and generates seismic waves that cause bulk density variations propagating with them. Both processes induce gravity perturbations whose signals propagate with the speed of light and therefore can arrive at remote stations earlier than the fastest elastic P wave. In turn, the gravity perturbations generate secondary seismic sources everywhere within the earth, a part of which around the observation locations can cause ground motion prior to the direct P wave arrival there, too. Recently, these so-called prompt elasto-gravity signals (PEGS) of large seismic events like the 2011 Mw 9.1 Tohoku earthquake have been detected using the data recorded by broadband seismometers and superconducting gravimeters. Though the physics of the PEGS has been well understood, the tools used so far for a realistic modelling of them are complicated and computationally intensive. In this study, we present a new and straightforward approach that solves the full-coupled elasto-gravitational boundary-value problem more accurately, but no more complicated than to compute synthetic seismograms in a conventional way. Using the new tool, we simulate the complete PEGS of the 2011 Tohoku earthquake based on a realistic kinematic finite-fault source model. Furthermore, we present a comprehensive investigation of potential uses of PEGS in modern seismology. As an example, we show particularly that the major source parameters like the moment magnitude, the rupture duration and the focal mechanism of a megathrust earthquake like the 2011 Tohoku earthquake can be estimated robustly using the measured PEGS data. © 2020 Elsevier B.V.
关键词	2011 Tohoku earthquake early warning earthquake source inversion elasto-gravitational coupling synthetic seismograms
英文关键词	Boundary value problems; Faulting; Gravimeters; Seismic waves; 2011 tohoku earthquakes; Broad-band seismometers; Early warning; Earthquake source; Finite fault source model; Megathrust earthquakes; Superconducting gravimeter; Synthetic seismogram; Earthquakes; early warning system; earthquake mechanism; earthquake rupture; elastodynamics; focal mechanism; gravity field; P-wave; seismology; synthetic seismogram; tectonic setting; Tohoku earthquake 2011
语种	英语
来源期刊	Earth and Planetary Science Letters
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/203003
作者单位	School of Earth and Space Sciences, Peking University, Beijing, 100871, China; Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences, Potsdam, 14473, Germany
推荐引用方式 GB/T 7714	Zhang S.,Wang R.,Dahm T.,et al. Prompt elasto-gravity signals (PEGS) and their potential use in modern seismology[J],2020,536.
APA	Zhang S.,Wang R.,Dahm T.,Zhou S.,&Heimann S..(2020).Prompt elasto-gravity signals (PEGS) and their potential use in modern seismology.Earth and Planetary Science Letters,536.
MLA	Zhang S.,et al."Prompt elasto-gravity signals (PEGS) and their potential use in modern seismology".Earth and Planetary Science Letters 536(2020).